[2] The Oriental magpie's evolution as a distinct lineage started considerably earlier than the Gelasian date of c.2 million years ago (Ma) indicated by a molecular clock analysis.

The assumed divergence rate – 1.6% point mutations per Ma – is appropriate for a long-lived passerine, but hybridization – which as only mtDNA was used would be hard to detect – and the few specimens analyzed make the molecular clock estimate just an approximation.

Meanwhile, the fossil record of North American magpies has a specimen – UCMP 43386, a left tarsometatarsus from Palo Duro Falls (Randall County, Texas) – which is probably from the Early Pleistocene Irvingtonian age, around 2–1 Ma.

This was not used to calibrate the molecular clock analysis, but accounting for the phylogenetic hypothesis it appears more likely that the Korean magpie's ancestors diverged from other Pica in the Early Pliocene already, perhaps 5–4.5 Ma, antedating the uplift of the Sierra Nevada which cut off most gene flow between the two North American populations.

Eurasian magpie lineages) until the onset of the Quaternary glaciation some 2.6–2 Ma may also have skewed the molecular clock results.

The long tail might be plesiomorphic for this group, as it is also found in the tropical Asian magpies (Cissa and Urocissa) as well as in most of the very basal corvids, such as the treepies.

[7] In Korea, the magpie (까치, "kkachi") is celebrated as "a bird of great good fortune, of sturdy spirit and a provider of prosperity and development".